1. Field of the Invention
The present invention relates to an apparatus and a method for forming a winding for a dynamoelectric machine such as an automotive alternator, etc., and particularly relates to an apparatus and a method for forming a conducting wire end portion such as an output wire of a dynamoelectric stator winding, etc.
2. Description of the Related Art
Conventional stator winding end portion bending apparatuses are used in dynamoelectric machines in which coil segments are stacked and inserted into a plurality of slots of a stator core so as to form a plurality of coil layers, and in each of the coil layers, form open end portions of large numbers of coil segments that constitute the coil layers in question that project out of the slots by bending and twisting appropriately (see Patent Literature 1, for example).
In these conventional apparatuses, a plurality of cylindrical stratified ring belts have projecting portions that form a large number of holding grooves that hold tip end portions of the open end portions of the coil segments circumferentially on first edge portions in an axial length direction, and are disposed coaxially so as to leave a predetermined clearance radially.
Patent Literature 1: Japanese Patent Laid-Open No. 2004-135438 (Gazette)
However, in the conventional devices that are described above, details of an operation that presents many obstacles to achieving mass production, i.e., details of the complicated operation of inserting the tip end portions of the conductor end portions one by one into the corresponding holding grooves of the stratified ring belts, are not described at all. The protruding conductor end portions can sway relatively freely toward the tip ends and circumstances can arise in which these tip end portions dislodge from openings of the holding grooves as the tip end portions are being inserted into the holding grooves. That risk increases significantly if the conductor end portions have a circular cross section, in particular. Thus, since a means for reliably introducing and holding adjacent tip end portions of a plurality of conductor end portions into the holding grooves is required before the stratified ring belts can be used, overall productivity can hardly be said to have improved. This is a major obstacle when attempting to apply bending simultaneously to a plurality of conductor end portions.
In stators of this kind, a plurality of conductor end portions may also project outward from a stator core or tightly-packed coil ends in a state of close contact. The end portions of large numbers of continuous conductor wires project outward from the coil ends in a state of close contact particularly in stators that are configured by installing winding assemblies that are prepared by simultaneously folding large numbers of continuous conductor wires in a stator core in multiple layers. The conductor end portions that project out from the coil ends are often led around and formed so as to conform to arrangements or shapes of other conductor end portions that project out from the coil ends, rectifier apparatuses, connecting terminals, etc. However, because the conventional devices that are described above simultaneously bend and form the open end portions of large numbers of coil segments by holding them in holding grooves, they cannot be applied to stators in which the lead around shape differs for each of the conductor end portions.